Fix Square legend render bug.

src/src/Rendering/Legend/ResliceSquareLegendActor.cpp

@@ -18,17 +18,22 @@ vtkStandardNewMacro(ResliceSquareLegendActor)
 void ResliceSquareLegendActor::BuildShape(vtkRenderer *renderer) {
     int* sizes = renderer->GetSize();
     Square->SetDisplayPosition(sizes[0]-20,sizes[1]-20);
+    CheckSquare->SetDisplayPosition(sizes[0]-15,sizes[1]-15);
 }
 
 void ResliceSquareLegendActor::ReleaseGraphicsResources(vtkWindow * window) {
     Square->ReleaseGraphicsResources(window);
+    CheckSquare->ReleaseGraphicsResources(window);
 }
 
 int ResliceSquareLegendActor::RenderOverlay(vtkViewport *viewport) {
     auto renderer =  vtkRenderer::SafeDownCast(viewport);
     if (renderer){
         BuildShape(renderer);
-        return Square->RenderOverlay(viewport);
+        int ret = Square->RenderOverlay(viewport);
+        if (Checked)
+            CheckSquare->RenderOverlay(viewport);
+        return ret;
     }
     return 0;
 }
@@ -43,9 +48,9 @@ ResliceSquareLegendActor::ResliceSquareLegendActor() {
     vtkNew<vtkPoints> pts;
     pts->SetNumberOfPoints(4);
     pts->SetPoint(0,0,0,0);
-    pts->SetPoint(1,18,0,0);
-    pts->SetPoint(2,18,18,0);
-    pts->SetPoint(3,0,18,0);
+    pts->SetPoint(1,20,0,0);
+    pts->SetPoint(2,20,20,0);
+    pts->SetPoint(3,0,20,0);
     polydata->SetPoints(pts);
     vtkNew<vtkPolygon> polygon;
     polygon->GetPointIds()->SetNumberOfIds(4);
@@ -64,6 +69,35 @@ ResliceSquareLegendActor::ResliceSquareLegendActor() {
     Square->GetProperty()->SetLineWidth(0);
     Square->GetProperty()->SetPointSize(0);
 
+    CheckSquare =  vtkActor2D::New();
+    CheckSquare->Register(this);
+    CheckSquare->Delete();
+    vtkNew<vtkPolyDataMapper2D> mapper2;
+    vtkNew<vtkPolyData> polydata2;
+    vtkNew<vtkPoints> pts2;
+    pts2->SetNumberOfPoints(4);
+    pts2->SetPoint(0,0,0,0);
+    pts2->SetPoint(1,10,0,0);
+    pts2->SetPoint(2,10,10,0);
+    pts2->SetPoint(3,0,10,0);
+    polydata2->SetPoints(pts2);
+    vtkNew<vtkPolygon> polygon2;
+    polygon2->GetPointIds()->SetNumberOfIds(4);
+    polygon2->GetPointIds()->SetId(0,0);
+    polygon2->GetPointIds()->SetId(1,1);
+    polygon2->GetPointIds()->SetId(2,2);
+    polygon2->GetPointIds()->SetId(3,3);
+
+    vtkNew<vtkCellArray> cells2;
+    cells2->InsertNextCell(polygon2);
+
+    polydata2->SetPolys(cells2);
+    mapper2->SetInputData(polydata2);
+    CheckSquare->SetMapper(mapper2);
+
+    CheckSquare->GetProperty()->SetLineWidth(0);
+    CheckSquare->GetProperty()->SetPointSize(0);
+
 }
 
 ResliceSquareLegendActor::~ResliceSquareLegendActor() {

src/src/Rendering/Legend/ResliceSquareLegendActor.h

@@ -53,6 +53,9 @@ public:
     vtkTypeBool HasTranslucentPolygonalGeometry() override { return 0; }
 
     vtkProperty2D* GetProperty();
+
+    vtkSetMacro(Checked,bool);
+    vtkGetMacro(Checked,bool);
 protected:
     ResliceSquareLegendActor();
 
@@ -64,6 +67,9 @@ private:
     void operator=(const ResliceSquareLegendActor &) = delete;
 
     vtkActor2D * Square;
+    vtkActor2D * CheckSquare;
+
+    bool Checked = false;
 };